In the industrial systems, in particular machines and machine systems, a large number of electrical low-voltage loads must be supplied with electrical power. The loads are often, but not necessarily, single-phase or three-phase AC voltage motors. A 500 V DC voltage, for example, supply is also known.
In the past, power was distributed to the loads in switchgear cabinets in which the feed module for the loads was also arranged. Separate cables were routed from the switchgear cabinet to the individual loads. A cable system thus had a star-like topology. On the basis of this topology, namely with a separate cable for each load, it was relatively simple to design the cables. This work could be done even by electricians using comparatively simple tables.
Recently, the electrical loads have been connected to an ever greater extent to the feed module via cable systems similar to busses or networks. A bus section of the cable system thus originates from the feed module, via which a network—which possibly may even have further branches—is passed to the individual loads. The bus section carries all the current for the connected loads. Further sections branch off to the individual loads, and these are referred to in the following text as single or end sections, which carry the current for only this single load.
The PCT application “Computer-aided test procedure for a cable system” (internal file reference 2000 P 03188 WO, priority date Mar. 20, 2000, priority file reference 100 13 521.8), which was submitted on the same date as the present application, describes a test procedure for a bus-like or network-like cable system, by which it is possible to check that the design of the cable system is adequate, and by which this cable system may even possibly be designed automatically. However, the topology of the cable system as such is not changed.
In the method described above, it is possible for the feed module to be arranged poorly by the user. This leads to disadvantages during operation of the cable system and, in the extreme, even to the possibility of the cable system no longer being adequately designed or no longer being correctly configurable.